Gliosarcoma with angiosarcomatous features: a case report.

A surgical case of gliosarcoma in which the mesenchymal component showed angiosarcomatous features is reported. The neoplasm was extirpated from the right cerebral hemisphere of a 76-year-old man who presented with left hemiparesis and headache, and it was composed of both anaplastic astrocytomatous and sarcomatous elements. The sarcomatous element was composed of a proliferation of atypical endothelial cells that had pleomorphic, mitotically active nuclei and formed vascular lumina of irregular shapes or solid cellular sheets, and was accompanied by the deposition of collagenous matrix. The cytoplasm of some of the atypical endothelial cells was immunohistochemically positive for vimentin, factor VIII-related antigen, CD 34, and thrombomodulin. The MIB-1 labeling index of the sarcomatous component was higher than that of the astrocytomatous component.